Cytochrome b5 Reductase 2 (CYB5R2)

Cytochrome b5 reductase 2 (CYB5R2), a member of the flavoprotein pyridine nucleotide cytochrome reductase family, is associated with a number of physiological reactions. However, its role in cancer, especially nasopharyngeal carcinoma (NPC), has not been addressed. The transcript levels and promoter methylation status of CYB5R2 in NPC derived cell lines and tumor biopsies and experimentally address its role as a tumor suppressor gene. CYB5R2 transcript levels are decreased in NPC cell lines and tumor biopsies. Promoter hypermethylation of CYB5R2 was detected in all six tested NPC cell lines and in 84 % of primary NPC tumor biopsies but not in normal nasopharyngeal epithelium. Unlike CYB5R3 and CYB5R1, CYB5R2 has no N-terminal membrane anchor.